package com.x25175.file.util;


import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;

import java.util.HashSet;
import java.util.Set;

/**
 * @author 徐佳辉
 * @date 2020/11/23 10:37
 * BeanUtils.copyProperties可以忽略空的字段
 * BeanUtils.copyProperties(studentVo, student, IgnoreNullUtil.getNullPropertyNames(studentVo));
 */
public class IgnoreNullUtil {


    public static String[] getNullPropertyNames (Object source) {
        final BeanWrapper src = new BeanWrapperImpl(source);
        java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();

        Set<String> emptyNames = new HashSet<String>();
        for(java.beans.PropertyDescriptor pd : pds) {
            Object srcValue = src.getPropertyValue(pd.getName());
            if (srcValue == null) emptyNames.add(pd.getName());
        }
        String[] result = new String[emptyNames.size()];
        return emptyNames.toArray(result);
    }
}
